Rock Engineering
Rock Mass Classification Tool
Determine rock mass quality and engineering ratings using Bieniawski (1989) RMR89, Barton (1974) Q-System, and Hoek (2013) Geological Strength Index (GSI) matrix.
Rock Mass Classification Tool
Determine rock mass quality and engineering ratings using Bieniawski (1989) RMR89, Barton (1974) Q-System, and Hoek (2013) Geological Strength Index (GSI) matrix.
Inputs
RMR89 Parameter Ratings (Bieniawski, 1989)
Results
Classification Results
Make a selection for every parameter above, or load a demo, to see the classification.
Theory and formulae
Rock Mass Classification Equations
About this calculator
This free rock mass classification calculator runs entirely in your browser: what you enter is never uploaded. Use the calculation steps and the theory section to check the working, and print a calculation sheet with the inputs, results and formulae for your records.
Methods and references: RMR89, Q-System 1974, GSI 2013.
Topics: rock mass, rmr, q-system, gsi, bieniawski, barton, hoek, tunneling, rock mechanics.
Engineering notice: Results are for preliminary estimation, screening and education. All inputs and outputs must be independently verified by a qualified professional engineer before use in any design or construction decision. Read the full disclaimer
Disclaimer
This calculation sheet was generated with Geotechnical Toolbox for preliminary estimation, screening, educational and verification purposes only. Geotechnical engineering involves site-specific ground conditions and uncertainty. All inputs, methods, results and figures must be independently checked and approved by a qualified Professional Engineer (P.Eng. / PE) before being relied on for design, construction or any safety-critical decision. Results reflect the values entered at the time of printing. The author and site accept no liability for errors, omissions or damages arising from their use.
Open this calculator online: geotechnica.ca/tools/rock-mass-classification
© 2026 Geotechnical Toolbox
geotechnica.ca